diff options
Diffstat (limited to 'kernel/dma')
| -rw-r--r-- | kernel/dma/pool.c | 122 |
1 files changed, 84 insertions, 38 deletions
diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index db4f89ac5f5f..ffe866c2c034 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -9,13 +9,17 @@ #include <linux/init.h> #include <linux/genalloc.h> #include <linux/slab.h> +#include <linux/workqueue.h> static struct gen_pool *atomic_pool_dma __ro_after_init; static struct gen_pool *atomic_pool_dma32 __ro_after_init; static struct gen_pool *atomic_pool_kernel __ro_after_init; #define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K -static size_t atomic_pool_size __initdata = DEFAULT_DMA_COHERENT_POOL_SIZE; +static size_t atomic_pool_size = DEFAULT_DMA_COHERENT_POOL_SIZE; + +/* Dynamic background expansion when the atomic pool is near capacity */ +static struct work_struct atomic_pool_work; static int __init early_coherent_pool(char *p) { @@ -24,76 +28,116 @@ static int __init early_coherent_pool(char *p) } early_param("coherent_pool", early_coherent_pool); -static int __init __dma_atomic_pool_init(struct gen_pool **pool, - size_t pool_size, gfp_t gfp) +static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, + gfp_t gfp) { - const unsigned int order = get_order(pool_size); - const unsigned long nr_pages = pool_size >> PAGE_SHIFT; + unsigned int order; struct page *page; void *addr; - int ret; + int ret = -ENOMEM; + + /* Cannot allocate larger than MAX_ORDER-1 */ + order = min(get_order(pool_size), MAX_ORDER-1); + + do { + pool_size = 1 << (PAGE_SHIFT + order); - if (dev_get_cma_area(NULL)) - page = dma_alloc_from_contiguous(NULL, nr_pages, order, false); - else - page = alloc_pages(gfp, order); + if (dev_get_cma_area(NULL)) + page = dma_alloc_from_contiguous(NULL, 1 << order, + order, false); + else + page = alloc_pages(gfp, order); + } while (!page && order-- > 0); if (!page) goto out; arch_dma_prep_coherent(page, pool_size); - *pool = gen_pool_create(PAGE_SHIFT, -1); - if (!*pool) - goto free_page; - addr = dma_common_contiguous_remap(page, pool_size, pgprot_dmacoherent(PAGE_KERNEL), __builtin_return_address(0)); if (!addr) - goto destroy_genpool; + goto free_page; - ret = gen_pool_add_virt(*pool, (unsigned long)addr, page_to_phys(page), - pool_size, -1); + ret = gen_pool_add_virt(pool, (unsigned long)addr, page_to_phys(page), + pool_size, NUMA_NO_NODE); if (ret) goto remove_mapping; - gen_pool_set_algo(*pool, gen_pool_first_fit_order_align, NULL); - pr_info("DMA: preallocated %zu KiB %pGg pool for atomic allocations\n", - pool_size >> 10, &gfp); return 0; remove_mapping: dma_common_free_remap(addr, pool_size); -destroy_genpool: - gen_pool_destroy(*pool); - *pool = NULL; free_page: - if (!dma_release_from_contiguous(NULL, page, nr_pages)) + if (!dma_release_from_contiguous(NULL, page, 1 << order)) __free_pages(page, order); out: - pr_err("DMA: failed to allocate %zu KiB %pGg pool for atomic allocation\n", - pool_size >> 10, &gfp); - return -ENOMEM; + return ret; +} + +static void atomic_pool_resize(struct gen_pool *pool, gfp_t gfp) +{ + if (pool && gen_pool_avail(pool) < atomic_pool_size) + atomic_pool_expand(pool, gen_pool_size(pool), gfp); +} + +static void atomic_pool_work_fn(struct work_struct *work) +{ + if (IS_ENABLED(CONFIG_ZONE_DMA)) + atomic_pool_resize(atomic_pool_dma, + GFP_KERNEL | GFP_DMA); + if (IS_ENABLED(CONFIG_ZONE_DMA32)) + atomic_pool_resize(atomic_pool_dma32, + GFP_KERNEL | GFP_DMA32); + atomic_pool_resize(atomic_pool_kernel, GFP_KERNEL); +} + +static __init struct gen_pool *__dma_atomic_pool_init(size_t pool_size, + gfp_t gfp) +{ + struct gen_pool *pool; + int ret; + + pool = gen_pool_create(PAGE_SHIFT, NUMA_NO_NODE); + if (!pool) + return NULL; + + gen_pool_set_algo(pool, gen_pool_first_fit_order_align, NULL); + + ret = atomic_pool_expand(pool, pool_size, gfp); + if (ret) { + gen_pool_destroy(pool); + pr_err("DMA: failed to allocate %zu KiB %pGg pool for atomic allocation\n", + pool_size >> 10, &gfp); + return NULL; + } + + pr_info("DMA: preallocated %zu KiB %pGg pool for atomic allocations\n", + gen_pool_size(pool) >> 10, &gfp); + return pool; } static int __init dma_atomic_pool_init(void) { int ret = 0; - int err; - ret = __dma_atomic_pool_init(&atomic_pool_kernel, atomic_pool_size, - GFP_KERNEL); + INIT_WORK(&atomic_pool_work, atomic_pool_work_fn); + + atomic_pool_kernel = __dma_atomic_pool_init(atomic_pool_size, + GFP_KERNEL); + if (!atomic_pool_kernel) + ret = -ENOMEM; if (IS_ENABLED(CONFIG_ZONE_DMA)) { - err = __dma_atomic_pool_init(&atomic_pool_dma, - atomic_pool_size, GFP_DMA); - if (!ret && err) - ret = err; + atomic_pool_dma = __dma_atomic_pool_init(atomic_pool_size, + GFP_KERNEL | GFP_DMA); + if (!atomic_pool_dma) + ret = -ENOMEM; } if (IS_ENABLED(CONFIG_ZONE_DMA32)) { - err = __dma_atomic_pool_init(&atomic_pool_dma32, - atomic_pool_size, GFP_DMA32); - if (!ret && err) - ret = err; + atomic_pool_dma32 = __dma_atomic_pool_init(atomic_pool_size, + GFP_KERNEL | GFP_DMA32); + if (!atomic_pool_dma32) + ret = -ENOMEM; } return ret; } @@ -142,6 +186,8 @@ void *dma_alloc_from_pool(struct device *dev, size_t size, ptr = (void *)val; memset(ptr, 0, size); } + if (gen_pool_avail(pool) < atomic_pool_size) + schedule_work(&atomic_pool_work); return ptr; } |